package number;

public class add1 {
	public static void main(String args[]) {
		
		        double sum = 0,item = 1;  
		        int i = 1,n = 20;  
		        while(i<=n) {  
		            sum = sum+item;  
		            i = i+1;  
		            item = item*(1.0/i);  
		        }  
		        System.out.println("sum="+sum);  
	
	}
}
